FIG. 1 shows a general gearshift of an electric car to which the present disclosure can be applied, in which a motor M is connected to an input shaft IN for supplying power and an output shaft OUT is parallel to the input shaft IN. A first driving gear 1D and a first driven gear 1P are installed on the input shaft IN and output shaft OUT and are interlocked. A second driving gear 2D and a second driven gear 2P are also installed on the input shaft and the output shaft and interlocked.
A synchronizer is mounted to the output shaft OUT between the first and second driven gears 1P and 2P to connect or disconnect the first and second driven gears 1P and 2P to or from the output shaft OUT. A cone clutch CC is arranged between the second driven gear 2P and the output shaft OUT to enable power transmission by friction.
The motor M, the synchronizer, and the cone clutch CC are controlled by a controller C.
Alternatively, the synchronizer and the cone clutch CC may be installed on the input shaft IN to form a gearshift, and the present disclosure is also available to the gearshift.
As such, the gearshift may use the cone clutch CC in gear shifting to prevent torque interruption, which blocks torque from being transmitted to the output shaft OUT from the input shaft IN while shifting gears. In this case, shift quality depends on how the cone clutch CC is controlled, so that a need exists to control the cone clutch CC to maximize the shift quality.
For example, when gear shifting is made from a first gear to a second gear, the synchronizer changes the first driven gear 1P into a neutral condition from a connection state to the output shaft OUT and then changes the second driven gear 2P into the connection state to the output shaft OUT, and in between, drives the cone clutch to constantly transmit torque to the output shaft OUT from the input shaft IN using frictional force. In this case, the torque at the output shaft OUT needs to change from state A′ into state B′ as the first gear is shifted to the second gear as shown in FIG. 2, and during this change, it is beneficial for securing the shift quality when the torque changes linearly as shown in FIG. 2.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.